I arrived in Sydney this morning. Not only is this my first time in Australia, it's my first time in a place where cars drive on the left side of the road. I took a cab from the airport, so I didn't have to deal with it from behind the wheel, but it still seemed very odd visually. Still, it was pretty much what I had anticipated.
What I didn't anticipate, though, was how different it would be as a pedestrian. When crossing the street, I reflexively turned to the left to look for oncoming traffic, and seeing none, began to cross... until I heard something coming from my right! The reversed traffic flow meant that I had to re-learn how to cross a street!
There is another, much more subtle effect of this that I noticed as a pedestrian: when walking along the sidewalk, I naturally keep to the right, but here more often than not, people keep to the left while walking, too. I suppose that makes sense, given the convention for automobiles, but it was surprising nonetheless. It's striking how such small differences can change your routine so dramatically by making you focus on things you would normally take for granted.